The 2013 49ers were a team with very few holes. Few were surprised when Jim Harbaugh‘s squad progressed all the way to the NFC Championship Game before falling to the soon-to-be Super Bowl champion Seahawks. Although Colin Kaepernick was solid throughout the season, he was no longer the lightning rod he had been in 2012 when he led the team to Super Bowl XLVII before falling to the Ravens.

The offense received a major shot in the arm with the Week 13 return of Michael Crabtree from a long-term Achilles injury. The additional threat that Crabtree provided opposing defenses was enough to open up holes for the rushing attack, which was vital for the successful operation of Harbaugh’s run-first offense.

The defense, which boasted five 2013 Pro Bowlers, was one of the best units in the entire NFL. Former blue-chip flameout Glenn Dorsey appears to have found a home at the interior of Vic Fangio‘s 3-4 base defense. The linebacking corps, led by interior Pro Bowl duo NaVorro Bowman and Patrick Willis, was as good as any in the league. In the secondary, Donte Whitner was the group’s largest contributor and leader. Heading into the offseason, the team had to confront the expiring contracts of several potentially expensive players, and the 2014 roster will have a slightly different look to it because of that.

Offensively, the 49ers made dramatic strides at the receiver position during the offseason. They retained Anquan Boldin, traded for Stevie Johnson, signed Brandon Lloyd, and drafted deep threat Bruce Ellington. Frank Gore, who has the second-most rushing attempts among all active running backs, has been surrounded with several intriguing talents to lighten this year’s load. Perennial spell back Kendall Hunter will be joined by second-round pick Carlos Hyde, LaMichael James, and former South Carolina standout Marcus Lattimore.

The team extended Kaepernick through 2020, giving the Nevada alum a six-year, $114MM deal. Along the line, the team re-structured the deal of stalwart left tackle Joe Staley, ensuring the protection of Kaepernick’s blind side for the foreseeable future. Daniel Kilgore, who spent two years learning the 49ers offense while backing up Jonathan Goodwin, will look to finally start at center. The team also traded for Jonathan Martin, a hometown Stanford alum, who possesses higher upside than most NFL swingmen. The absences of the team’s two holdouts, Vernon Davis and Alex Boone, would be significant blows to the entire offense should their messy contract situations carry into the regular season.

Defensively, the biggest transition will be made in the secondary — Eric Reid is the only projected returning starter heading into training camp. He will likely be joined by Tramaine Brock, Chris Culliver, who’s returning from an ACL injury, and former Colt Antoine Bethea. The club brought in Bethea to replace the veteran safety void left by Whitner, who departed to Cleveland. First-round draft pick Jimmie Ward is the favorite to line up as nickel back.

The linebacking corps will take on a fairly new dynamic with the absence of Bowman and possibly Aldon Smith, whose legal woes could result in suspensions. Given their intriguing collection of linebackers, including Michael Wilhoite and Nick Moody and rookies Chris Borland and Shayne Skov, another Stanford alum, the 49ers will have many solid options. The line will again feature Justin Smith, with Ray McDonald playing opposite Smith and Dorsey lined up at nose tackle.

The 2013 49ers came a few plays away from back-to-back Super Bowl berths. That team managed to improve dramatically on offense and more or less hold the line defensively this past offseason, which makes the Niners a serious Super Bowl contender heading into 2014. The team’s regular season matchups against the Seahawks will be two of the season’s most anticipated games, and for good reason — one could reasonably expect the NFC West rivals to meet again in the NFC Championship.